2-amino-3-aroyl-γ-oxobenzenebutanoic acid and esters

ABSTRACT

2-Amino-3-aroyl-γ-oxobenzenebutanoic acids and derivatives having the formula: ##STR1## wherein X is hydrogen, halogen, or loweralkyl; Y is hydrogen, halogen, loweralkyl, loweralkoxyl, nitro, or trifluoromethyl; n is 1 or 2; and R is hydrogen lower-alkyl, or a pharmaceutically acceptable cation, are disclosed having anti-inflammatory activity.

This is a division of application Ser. No. 06/900,599, filed Aug. 26,1986, U.S. Pat. No. 4,782,089.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to novel2-amino-3-aroyl-γ-oxobenzenebutanoic acids, novel methods of preparationthereof, novel intermediates therefor, and pharmaceutical methods andcompositions for treating living animals for pain and inflammationtherewith.

2. Description of the Prior Art

2-Amino-3-aroyl-benzeneacetic acids, esters, and metal salts thereofhave been disclosed as having anti-inflammatory activity in U.S. Pat.No. 4,045,576 and as having anti-inflammatory and analgesic activity bySancilio, L. F. et al. in AGENTS AND ACTIONS, Vol. 7/1 (1977) BirkauserVerlag Basel Schweiz. These compounds do not have a keto group of thealkanoic acid chain. 3-Aroyl-γ-oxobenzenebutanoic acids have beendisclosed in U.S. Pat. No. 3,784,701 as having anti-inflammatory andanalgesic activity. These compounds do not have a 2-amino group on theprimary benzene ring as do the compounds of the present invention.

SUMMARY OF THE INVENTION

The novel 2-amino-3-aroyl-γ-oxobenzenebutanoic acids of this inventionhave the formula: ##STR2## wherein X is selected from hydrogen, halogen,or lower-alkyl; Y is selected from hydrogen, halogen, loweralkyl,loweralkoxy, nitro, or trifluoromethyl; n is 1 or 2; R is H, loweralkyl,or a pharmaceutically acceptable cation.

In the further definition of symbols and in the formulas hereof andwhere they appear elsewhere throughout this specification and in theclaims, the terms have the following significance.

The term "loweralkyl" as used herein, unless otherwise specified,includes straight and branched chain radicals of up to eight carbonsinclusive and is exemplified by such groups as methyl, ethyl, propyl,isopropyl, butyl, sec. butyl, tert. butyl, amyl, isoamyl, hexyl, heptyl,and octyl radicals, and the like. The term "loweralkoxy" has the formula--O--loweralkyl.

The terms "halo" or "halogen" as used herein includes fluorine,chlorine, bromine, and iodine. Preferably, the halogen is chlorine orbromine.

The term "pharmaceutically acceptable cation" includes cations selectedfrom such as sodium, potassium, calcium, magnesium, zinc, aluminum,copper, and the hydrates of the salts formed therewith when they occur.

The compounds of the present invention are useful in controllinginflammation and pain and in inhibiting blood platelet aggregation.

The anti-inflammatory utility of the novel compounds of this inventionwas determined using a modification of the Evans Blue-CarrageenanPleural Effusion Assay of Sancilio, L. F., J. PHARMACOL. EXP. THER. 168,199-204 (1969), and a modification of the Adjuvant-Induced ArthritisMethod of Walz, D. T. et al., J. PHARMAC. EXP. THER. 178, 223-231(1971). See Pharmacology hereinbelow for description of tests.

The analgesic utility of the compounds of Formula I was determined by amodification of the method of Collier et al., J. BR. PHARMAC. CHEMOTHER.32, 295-310 (1968). (See Pharmacology hereinbelow for description oftest).

Novel intermediates used in the preparation of compounds of Formula Iare the compounds of Formulas II, III and IV below. ##STR3## wherein Xand Y are as defined under Formula I; R¹ and R² are selected fromloweralkyl or, when taken together with the adjacent nitrogen atom, mayform a heterocyclic amine selected from 1-pyrrolidinyl, 1-piperidinyl or4-morpholinyl; and R⁴ is selected from hydrogen, loweralkyl or a metalcation selected from sodium, potassium, barium or calcium.

The compounds of Formula I are pharmacologically activeanti-inflammatory analgesic prodrugs of 2-amino-3-benzoyl-benzeneaceticacids described in U.S. Pat. No. 4,045,576 and as such are capable ofproviding effectiveness in controlling inflammation and pain in livinganimals at a later time interval than the benzeneacetic acids. Theeffectiveness as an anti-inflammatory and analgesic of3-benzoyl-benzeneacetic acid (AHR-5850) is described by Sancilio, L. F.et al. in AGENTS AND ACTIONS (See reference above).

It is therefore an object of the present invention to provide novelcompounds via novel intermediates and compositions useful in the controlof inflammation, pain, and blood-platelet aggregation.

A further object is to provide prodrugs which break down to the2-amino-3-benzoyl-benzeneacetic acids after administration to livinganimals which are primarily responsible for the pharmacologicalactivity, thus providing a more gradual and longer lasting effect thanwould be obtained from administration of the2-amino-3-benzoyl-benzeneacetic acids.

Additional objects will be apparent to one skilled in the art and stillother objects will be apparent hereinafter.

DETAILED DESCRIPTION OF THE INVENTION

The compounds of Formula I are prepared by reactions represented byequations given in Chart I. ##STR4##

The 2-amino-3-aroyl-γ-oxobenzenebutanoic acids and esters are preparedby a novel method comprising the following sequence of steps:

Step 1, reacting an indole having the formula: ##STR5## wherein X, Y andn are as defined under Formula I with formaldehyde and an amine havingthe formula: ##STR6## wherein R¹ and R² are selected from loweralkyl orwhen taken together with the nitrogen atom, may form a heterocyclicamine such as 1-pyrrolidinyl, 1-piperidinyl or 4-morpholinyl to give acompound having the formula: ##STR7## wherein X, Y, n, R¹ and R² havethe starting values,

Step 2, reacting the compound prepared in Step 1 with an alkali-metalsalt of a diloweralkyl ester of malonic acid having the formula:

    MCH(COOR.sup.3).sub.2

wherein M is an alkali-metal and R³ l is loweralkyl to give a compoundhaving the formula: ##STR8## wherein X, Y, n and R³ have the valuesassigned above,

Step 3, de-esterifying a compound prepared in Step 2 by heating it inaqueous basic solution and thereafter adding acid to give a compound ofthe formula: ##STR9## wherein X, Y, and n have the values assignedabove,

Step 4, decarboxylating a compound prepared in Step 3 by heating toliberate carbon dioxide to give a compound having the formula: ##STR10##wherein X, Y and n have the values assigned above,

Step 5, oxidizing a compound prepared in Step 4 with ozone to give acompound having the formula: ##STR11## wherein R is hydrogen orloweralkyl and X, Y, and n have the values assigned above and thereafterdecomposing excess ozone,

Step 6, esterifying a compound prepared in Step 5 with a loweralkanolwherein R is H to give a compound wherein R is loweralkyl

Step 7, de-esterifying a compound prepared in Step 5 wherein R isloweralkyl by hydrolysis in aqueous base and neutralizing with a strongacid.

In reference to the process steps summarized above as they apply to thepreparation of compounds of Formulas I, II, III, and IV, the followingfurther description is applicable:

In Step 1, illustrated by the preparation of Intermediates 1 and 5, anaqueous solution of the HNR¹ R² amine and formaldehyde solution arereacted in the cold ca. 0°-10° C. and added to a mixture of the7-benzoyl-1H-indole in acetic acid. Ethanol is added to the mixturewhich is then warmed. The preferred amine is dimethylamine as any excessamine is easily evaporated off.

The product is separated by partitioning into the organic phase of amixture of aqueous base and a solvent such as methylene chloride andevaporating the solvent and recrystallizing.

In Step 2, illustrated by the preparation of Intermediates 2 and 6, the3-aminoalkyl-indolo-phenylmethanone is reacted with diloweralkylalkali-metal malonate formed, for example, by sodium hydride anddiloweralkyl malonate ester by refluxing in an aprotic solvent such asxylene until reaction has occurred. The product is isolated byconventional means such as evaporation of solvent and recrystallizing orby high pressure liquid chromatography.

In Step 3, illustrated by the preparation of Intermediates 3 and 7, thepropanedioic acid ethyl ester derivatives is heated in intermediatestrength base such as 3N sodium hydroxide. Other bases (MOH) which aresuitable are those such as potassium, calcium, and barium hydroxides. Atthis point the liberated propanedioic acid is in the form of its metalsalt corresponding to the base used. A strong acid such as hydrochloricacid is added to give the free propanedioic acid derivative and theproduct is separated by conventional precipitation and filtration.

In Step 4, illustrated by the preparation of Intermediates 4 and 8, thepropanedioic acid derivative is heated at about 180°-210° C. underreduced pressure until liberation of carbon dioxide ceases. The productis obtained by cooling the resulting melt.

In Step 5, illustrated by Examples 1 and 2, the propanoic acidderivative is oxidized with ozone in a mixture of ethanol and ethylacetate. Aqueous potassium iodide is added. Liberated iodine is removedby washing with sodium thiosulfate solution and the organic layer isconcentrated. The residue is dissolved in a suitable solvent; e.g.,ethanol, and heated with 6N hydrochloric acid under reflux. The solutionis again concentrated and the residue is partitioned between diluteaqueous base and methylene chloride and the product is isolated byconventional means. In this step, the more concentrated the initialsolution is, the more likely an ester will result.

Steps 6 and 7 are conventional esterification and de-esterificationsteps which are employed depending on whether an acid is obtained inStep 5 and an ester is desired or whether an ester is obtained in Step 5and an acid is desired.

Metal salts of acids obtained in Steps 5 or 7 may be obtained byconventional means.

The procedure for the synthesis of the starting indole derivatives is asdisclosed in U.S. Pat. No. 4,221,716. The route isindolines→7-benzoylidolines→7-benzoylindoles.

The following Intermediates 1-8 illustrates the synthesis of compoundsof Formulas II, III, and IV, and the following Examples 1-3 illustratethe synthesis of compounds of Formula I and should in no way be regardedas limiting, the limiting factors being only the definitions given underFormulas I, II, III, and IV. Variations in X and Y are brought about bystarting with the appropriate corresponding indole as would berecognizable by one skilled in the art.

INTERMEDIATE 1 [3-[(Dimethylamino)methyl]-1H-indol-7-yl]phenylmethanone

An 18.0 g (0.16 mole) portion of 40% aqueous dimethylamine was cooled to5° C. and 24 g (0.4 mole) of glacial acetic acid was added. To thismixture, held at 5° C., was added 12.2 g (0.15 mole) of 37% formalin.This aqueous mixture was added to a mixture of 33.1 g (0.15 mole) of7-benzoyl-1H-indole and 20 ml of acetic acid. After 100 ml of absoluteethanol was added to the mixture, it was warmed on a steam bath for 1/2hr. Isolation of the product was accomplished by concentrating themixture under reduced pressure, partitioning between dilute sodiumhydroxide and methylene chloride and concentrating the organic solution.The residue was recrystallized from isopropyl alcohol to give 29 g (70%) of light yellow crystals, m.p. 111.0°-113.5° C.

Analysis: Calculated for C₁₈ H₁₈ N₂ O: C, 77.67; H, 6.52; N, 10.06Found: C, 78.07; H, 6.49; N, 10.07.

INTERMEDIATE 2 2-[(7-Benzoyl-1H-indol-3-yl)methyl]propanedioic acid,diethyl ester

A mixture of 19.4 g (0.07 mole) of[3-[(dimethylamino)methyl]-1H-indol-7-yl]phenylmethanone and 32.5 g (0.2mole) of diethyl sodiomalonate prepared from 0.85 g (0.02 mole) of 57%sodium hydride in oil and 32 g (0.2 mole) of diethyl malonate in 50 mlof xylene was heated at reflux for 17 hr. The mixture was cooled,diluted with diethyl ether and washed with water. The solvent and excessreagents were removed by distillation at high vacuum. The residue wascrystallized first from isopropyl alcohol and then from isopropyl etherto give 12.6 g (46%) of light yellow powder, m.p. 86.0°-88.0° C.

Analysis: Calculated for C₂₃ H₂₃ NO₅ : C, 70.22; H, 5.89; N, b 3.56Found: C, 70.50; H, 5.93; N, 3.61.

INTERMEDIATE 3 2-[(7-Benzoyl-1H-indol-3-yl)methyl]propanedioic acid

A mixture of 10.0 g (0.025 mole) of2-[(7-benzoyl-1H-indol-3-yl)methyl]propanedioic acid diethyl ester in150 ml of 3N sodium hydroxide was heated at reflux for 18 hr, thentreated with charcoal, cooled and filtered. The dark yellow filtrate wasacidified by the dropwise addition of 50 ml of concentrationhydrochloric acid. The addition of 20 ml of methylene chloride caused byformation of a ppt., which was collected and recrystallized fromchloroform-methanol to give 6.0 g (70%) of off-white crystals, m.p.188°-189° C.

Analysis: Calculated for C₁₉ H₁₅ NO₅ : C, 67.65; H, 4.48; N, 4.15 Found:C, 67.91; H, 4.50; N, 4.20.

INTERMEDIATE 4 7-Benzoyl-1H-indole-3-propanoic acid

A 2.4 g (0.07 mole) sample of2-[(7-benzoyl-1H-indol-3-yl)methyl]propanedioic acid was heated at 190°C. under vacuum until carbon dioxide evolution ceased (1/2 hr). Thesyrup was cooled to give 2.1 g (100%) of a yellow solid, m.p.166.5°-168.5° C.

Analysis: Calculated for C₁₈ H₁₅ NO₃ : C, 73.71; H, 5.16; N, 4.78 Found:C, 73.76; H, 5.11; N, 4.84.

INTERMEDIATE 5(4-Chlorophenyl)-[3-[(dimethylamino)methyl]-1H-indol-7-yl]methanone

This compound was prepared by the procedure used to synthesize thecompound of Intermediate 1. A combination of 13.5 g (0.12 mole) of 40%aqueous dimethylamine, 16.5 g (0.275 mole) of acetic acid, 9.3 g (0.115mole) of 37% formalin, and 28.1 g (0.11 mole) of(4-chlorophenyl)(1H-indol-7-yl)methanone gave 35.3 g (99%) of crudetitle compound. Two recrystallizations of a small sample from 2-propanolgave white crystals, m.p. 95°-99° C.

Analysis: Calculated for C₁₈ H₁₇ ClN₂ O: C, 69.12; H, 5.48; N, 8.96Found: C, 69.27; H, 5.51; N, 8.82.

INTERMEDIATE 6 2-[[7-(4-Chlorobenzoyl)-1H-indol-3-yl]methyl]propanedioicacid, diethyl ester

This compound was prepared by the procedure used to synthesize thecompound of Intermediate 2, substituting dimethylsulfoxide to replacexylene as solvent. A combination of 4.2 g (0.1 mole) of 57% sodiumhydride, 30 ml of dimethyl sulfoxide, 80 g (0.5 mole) of diethylmalonateand 31.2 g (0.1 mole) of(4-chlorophenyl)[3-[(dimethylamino)methyl]-1H-indol-7-yl]methanone, gave45 g of crude title compound. A small sample (3.1 g) was purified byHPLC to give, after a recrystallization from 90% aqueous ethanol, 2.0 g(67%) of yellow crystals, m.p. 102.0°-102.5° C.

Analysis: Calculated for C₂₃ H₂₂ ClNO₅ : C, 64.56; H, 5.18; N, 3.27Found: C, 64.71; H, 5.21; N, 3.38.

INTERMEDIATE 7 2-[[7-(4-Chlorobenzoyl)-1H-indol-3-yl]methyl]propanedioicacid

This compound was prepared by the procedure used to synthesize thecompound of Intermediate 3. A batch of 28.8 g (0.067 mole) of2-[[7-(4-chlorobenzoyl)-1H-indol-3-yl]methyl]propanedioic acid diethylester and 600 ml of 3N sodium hydroxide gave, after a recrystallizationfrom chloroform-methanol, 19.5 g (79%) of pale yellow crystals, m.p.197°-201° C. with decomposition.

Analysis: Calculated for C₁₉ H₁₄ ClNO₅ : C, 61.38; H, 3.80; N, 3.77Found: C, 61.58; H, 3.81; N, 3.83.

INTERMEDIATE 8 7-(4-Chlorobenzoyl)-1H-indole-3-propanoic acid

This compound was prepared by the procedure used to synthesize thecompound of Intermediate 4. A batch of 18.9 g (0.51 mole) of2-[[7-(4-chlorobenzoyl)-1H-indol-3-yl]methyl]propanedioic acid heated to200° C. gave 16.6 g (100%) of a dark yellow solid, m.p. 190°-202° C.

Analysis: Calculated for C₁₈ H₁₄ ClNO₃ : C, 65.96; H, 4.31; N, 4.27Found: C, 66.13; H, 4.25; N, 4.28.

EXAMPLE 1 2-Amino-3-benzoyl-γ-oxobenzenebutanoic acid

A solution of 8.7 g (0.03 mole) of 7-benzoyl-1H-indole-3-propanoic acidin 300 ml of ethyl acetate and 100 ml of abs. ethanol was ozonized untilozone was present above the solution. The yellow solution was thentreated with 16.6 g (0.1 mole) of potassium iodide in 30 ml of aceticacid and 30 ml of water. After stirring 1 hr, the liberated iodine wasremoved by washing with a 15% sodium thiosulfate solution and the yelloworganic layer was concentrated. The residue was dissolved in 100 ml ofethanol and 20 ml of 6N hydrochloric acid and heated at reflux for 16hr. The dark red solution was concentrated and the residue waspartitioned between dil. sodium hydroxide and methylene chloride. Thebasic aqueous layer was made acidic and the pH was adjusted to 2-3 bythe addition of dil. sodium hydroxide. The solid was collected anddried, then recrystallized from benzene isopropyl ether to give 5.9 g(67 %) of yellow powder, m.p. 161.0°-2.5° C.

Analysis: Calculated for C₁₇ H₁₅ NO₄ : C, 68.68; H, 5.09; N, 4.71 Found:C, 68.82; H, 5.11; N, 4.67.

EXAMPLE 2 2-Amino-3-(4-chlorobenzoyl)-γ-oxobenzenebutanoic acid, ethylester

A solution of 13.1 g (0.04 mole) of7-(4-chlorobenzoyl)-1H-indole-3-propanoic acid in 450 ml of ethylacetate and 150 ml of absolute ethanol was treated with ozone untilozone was present above the solution. The solution was then stirred withan aqueous solution of potassium iodide, followed by a wash with aqueoussodium thiosulfate. The organic fraction was concentrated and theresidue was dissolved in 250 ml of 190 proof ethanol. The solution washeated to reflux, 150 ml of 6N hydrochloric acid was added, and heatingwas continued for 18 hr. The mixture was diluted with 400 ml of waterand a gummy solid separated. The gum was partitioned between dilutesodium hydroxide solution and methylene chloride. The basic aqueousfraction contained only a small amount of acidic material underacidification, so it was discarded. The methylene chloride layer wasdried over anhydrous sodium sulfate and passed through a column ofsilica gel. The yellow-colored eluant was concentrated and thecrystalline residue was recrystallized from cyclohexane to give 3.5 g(26%) of bright yellow powder, m.p. 112°-115° C.

Analysis: Calculated for C₁₉ H₁₈ ClNO₄ : C, 63.43; H, 5.04; N, 3.89Found: C, 63.52; H, 5.04; N, 3.92.

EXAMPLE 3 2-Amino-3-(4-chlorobenzoyl)-γ-oxobenzenebutanoic acid

A solution of 3.3 g (0.0092 mole) of2-amino-3-(4-chlorobenzoyl)-γ-oxobenzenebutanoic acid ethyl ester in 70ml of hot 190 proof ethanol was treated with 40 ml of 4N aqueous sodiumhydroxide solution and the mixture was heated at reflux for 18 hr. Thehot mixture was filtered and the insoluble material was discarded. Thefiltrate was cooled and the precipitate collected by filtration. Thisprecipitate was partitioned between dilute hydrochloric acid andmethylene chloride. The organic layer was separated, dried overmagnesium sulfate and concentrated to give 2.7 g (89%) of bright yellowcrystals, m.p. 172°-177° C.

Analysis: Calculated for C₁₇ H₁₄ ClNO₄ : C, 61.55; H, 4.25; N, 4.22Found: C, 61.43; H, 4.24; N, 4.24.

PHARMACOLOGY Acute Anti-inflammatory Test-Evans Blue-Carrageenen PleuralEffusion Assay

The method is that of Sancilio and Fishman in TOXICOL. APPL. PHARMAC.26, 575-584 (1973). Fasted Sprague-Dawley male rats, weighing between250-500 g were randomly divided into control and experimental groups ofsix animals one hour after oral administration of the compounds, e.g.,Formula I compounds or indomethacin, the rats were etherized and 5 ml ofa mild irritant solution (0.075% Evans blue and 0.5% carrageenan type 7)was administered intrapleurally. Five hours later, the animals weresacrificed with carbon dioxide, pleural fluids were collected incalibrated centrifuge tubes and measured. Results were expressed as theaverage percent decrease in volume of pleural fluid from that of thecontrol group. The carrier was 0.5% Tween 80 in distilled water and wasalso the control article. Potency as compared to indomethacin wasdetermined by regressional analysis by the method of Bliss, C. (1951)VITAMIN METHODS VOL. 2, pp 445-610, Ed. by Gyorgy, N. Y. Academic Press.Using this procedure, it was determined that the compound of Example 1was 1.73 (0.78-3.62) times the potency of indomethacin or consideringthe overlap of confidence limits, it is about as potent as indomethacinin the foregoing pleural effusion anti-inflammatory assay over the rangeof 0.16 to 4.0 mg/kg body weight.

Chronic Anti-inflammatory Test-Adjuvant-Induced Arthritis Assay

A modification of the method of Walz et al, J. PHARMAC. EXP. THER. 178,pp 223-31 (1971), was used. This consisted of a therapeutic rather thana prophylactic dosing regimen.

Female Lewis Wistar rats, weighing between 150 and 235 g, were used. Onday 0 a tattoo was made on each leg at the point where the Achillestendom enters the gastrocnemius muscle. This served as a reference pointfor measuring the limb volume, plethysmographically. Several hourslater, 0.05 ml of a suspension of 1.5% Mycobacterium butyricum inmineral oil was injected into the subplantar surface of the right handfoot. On day 18 the hind limb volumes of both feet were determined.Animals with significant swelling of the uninjected feet were randomizedby block design into groups of seven or eight. They were dosed orallyfive days/week, starting on day 18, with the last dose being given onday 28. Twenty-four hours after the last dose, the edema of the injectedand uninjected feet was determined by difference. Results were expressedas milliliter of edema of the injected and uninjected feet.

In this test, the compound of Example 3 was found to be 0.86 (0.47-1.7)times as potent as indomethacin.

Analgesia Test--Acetylcholine-induced Abdominal Constriction in Mice

The method is a modification of that of Collier, H. O. J. et al., J. BR.PHARMAC. CHEMOTHER. 32, 295-310 (1968). Fed female mice are randomizedinto groups of 10. Group 1 received the control article (carrier) whichwas 0.5% Tween 80 in distilled water (10ml/kg). Test agent was suspendedin 10 ml/kg of the carrier and administered by gavage to the mice and180 min later acetylcholine bromide in 0.06% saline was administeredintraperitoneally. Immediately thereafter, each mouse was placed underan inverted 1-liter beaker and observed for 3 min for the presence ofabdominal constriction. The compound of Example 3 prevented abdominalconstriction in b 70% of the mice when administered at 4.0 mg/kg in 10ml/kg of the carrier. This compared to 60% blocked by 1.0 mg/kgindomethacin under the same conditions.

FORMULATION AND ADMINISTRATION

The present invention also contemplates novel therapeutic compositionscontaining the compounds of the invention as active ingredients.Effective quantities of any of the foregoing pharmacologically activecompounds may be administered to a living animal body in any one ofvarious ways; for example, orally as in capsules or tablets,parenterally in the form of sterile solutions or suspensions, and insome cases intravenously in the form of sterile solutions. In formingthe novel compositions of this invention, the active ingredient isincorporated in a suitable carrier, illustratively, a pharmaceuticalcarrier. Suitable pharmaceutical carriers which are useful informulating the compositions of this invention include starch, gelatin,glucose, magnesium carbonate, lactose, malt and the like. Liquidcompositions are also within the purview of this invention and suitableliquid pharmaceutical carriers include ethyl alcohol, propylene glycol,glycerine, glucose syrup and the like.

The pharmacologically active compounds may be advantageously employed ina unit dosage of from 0.1 to 250 milligrams or more depending on thesize of the animal. For example, a large animal such as a horse mayrequire tablets of 500-1000 milligrams active ingredient. The unitdosage may be given a suitable number of times daily so that the dailydosage may vary from 0.3 l to 450 milligrams. Five to 25 milligramsappears optimum per unit dose.

It is only necessary that the active ingredient constitute an effectiveamount, i.e., such that a suitable effective dosage will be obtainedconsistent with the dosage form employed. The exact individual dosagesas well as daily dosages will, of course, be determined according tostandard medical principles under the direction of a physician orveterinarian.

The active agents of the invention may be combined with otherpharmacologically active agents, or with buffers, antacids or the like,for administration and the proportion of the active agent in thecompositions may be varied widely.

The following are examples of compositions formed in accordance withthis invention.

1. Capsules

Capsules of 5 mg., 25 mg., and 50 mg. of active ingredient per capsuleare prepared. With the higher amounts of active ingredient, adjustmentmay be made in the amount of lactose.

    ______________________________________                                        Typical blend for                                                                              Per capsule,                                                 encapsulation    mg.                                                          ______________________________________                                        Active ingredient                                                                              5.0                                                          Lactose          296.7                                                        Starch           129.0                                                        Magnesium stearate                                                                             4.3                                                          Total            435.0 mg.                                                    ______________________________________                                    

Additional capsule formulations preferably contain a higher dosage ofactive ingredient and are as follows.

    ______________________________________                                                         Per capsule,                                                 Ingredients      mg.                                                          ______________________________________                                        Active ingredient                                                                              25.0                                                         Lactose          306.5                                                        Starch           99.2                                                         Magnesium stearate                                                                             4.3                                                          Total            435.0 mg.                                                    ______________________________________                                    

In each case, uniformly blend the selected active ingredient withlactose, starch, and magnesium stearate and encapsulated the blend.

2. Tablets

A typical formulation for a tablet containing 5.0 mg. of activeingredient per tablet follows. The formulation may be used for otherstrengths of active ingredient by adjustment of weight of dicalciumphosphate.

    ______________________________________                                                        Per tablet, mg.                                               ______________________________________                                        (1)    Active ingredient                                                                            5.0                                                     (2)    Corn starch    13.6                                                    (3)    Corn starch (paste)                                                                          3.4                                                     (4)    Lactose        79.2                                                    (5)    Dicalcium phosphate                                                                          68.0                                                    (6)    Calcium stearate                                                                             0.9                                                                           170.1 mg.                                               ______________________________________                                    

Uniformly blend 1, 2, 4, and 5. Prepare 3 as a 10 percent paste inwater. Granulate the blend with starch paste and pass the wet massthrough an eight mesh screen. The wet granulation is dried and sizedthrough a twelve mesh screen. The dried granules are blended with thecalcium stearate and pressed.

3. Injectable-2% sterile solutions.

    ______________________________________                                                     Per cc.                                                          ______________________________________                                        Active ingredient                                                                            20 mg.                                                         Preservative, e.g.,                                                           chlorobutanol  0.5% weight/volume                                             Water for injection                                                                          q.s.                                                           ______________________________________                                    

Prepare solution, clarify by filtration, fill into vials, seal andautoclave.

Various modifications and equivalents will be apparent to one skilled inthe art and may be made in the compounds, compositions, and method ofthe present invention without departing from the spirit or scopethereof, and it is therefore understood that the invention is to belimited only by the scope of the appended claims.

What is claimed is:
 1. A compound selected from the group having theformula: ##STR12## wherein; X is selected from hydrogen, halogen, orloweralkyl;Y is selected from hydrogen, halogen, loweralkyl, nitro,trifluoromethyl, or loweralkoxy; n is 1 or 2; and R³ is hydrogen orloweralkyl.
 2. The compound of claim 1 which is2-[(7-benzoyl-1H-indol-3-yl)methyl]propanedioic acid diethyl ester. 3.The compound of claim 1 which is2-[(7-benzoyl-1H-indol-3-yl)methyl]-propanedioic acid.
 4. The compoundof claim 1 which is2-[[7-(4-chlorobenzoyl)-1H-indol-3-yl]methyl]propanedioic acid diethylester.
 5. The compound of claim 1 which is2-[[7-(4-chlorobenzoyl)-1H-indol-3-yl]methyl]propanedioic acid.
 6. Acompound selected from the group having the formula: ##STR13## wherein;X is selected from hydrogen, halogen, or loweralkyl;Y is selected fromhydrogen, halogen, loweralkyl, nitro, trifluoromethyl, or loweralkoxy;and n is 1 or
 2. 7. The compound of claim 6 which is7-benzoyl-1H-indole-3-propanoic acid.
 8. The compound of claim 6 whichis 7-(4-chlorobenzoyl)-1H-indole-3-propanoic acid.